BEIJING, May 19, (Agencies): Beijing on Thursday rejected Pentagon accusations that a Chinese aircraft made an “unsafe” intercept of a spy plane in international air space, as tensions rise in the strategically vital South China Sea.

Rivalry between China and the United States is mounting in the disputed waterway, an important shipping route thought to be home to vast energy deposits, and which Beijing claims almost in its entirety.

The US Department of Defense (DoD) told reporters Wednesday that two Chinese tactical aircraft intercepted an American reconnaissance plane in an “unsafe” manner, without giving details.

Two Chinese aircraft tailed a US EP-3 reconnaissance plan as it “flew close” to the island province of Hainan, he said, but kept “a safe distance” and did not make “dangerous moves”.

Such US flights were a “severe threat” to Chinese security, he added, calling for Washington to stop them immediately.

The incident comes more than a decade after a collision between a Chinese fighter jet and a US Navy EP-3 which killed the Chinese pilot and forced the US aircraft to make an emergency landing on Hainan.

A 11-day standoff ensued as Beijing interrogated the 24 US crew, seriously straining relations between the countries, and China went on to hold the plane for several months.

Surveillance

The two have traded accusations and warnings over such surveillance flights in subsequent years.

Beijing has been building islets in the South China Sea into artificial islands with military facilities including radar systems and airstrips.

Regional neighbours such as Vietnam and the Philippines have rival claims and the United States says China’s assertions have no basis in law.

Washington — which has embarked on a foreign policy “pivot” towards Asia — fears Beijing is seeking to impose military controls over the entire area.

Much to Beijing’s annoyance, the US military has conducted several “freedom of navigation” operations, in which planes or ships pass within a 12-nautical-mile buffer around the Chinese installations.

The latest intercept came after the Pentagon and China had worked to reduce the risk of mishaps “by improved dialogue at multiple levels”.

“Over the past year, DoD has seen improvements in PRC actions, flying in a safe and professional manner,” the Pentagon spokesman said Wednesday, adding that the Department of Defense was “addressing the (intercept) through the appropriate diplomatic and military channels”.

The encounter also came days after China accused the US of distorting facts in a report on the Asian giant’s defence policy and warned Washington it had “severely damaged” trust between the superpowers.

In the annual report to Congress the Pentagon said Beijing had been using “coercive tactics” to assert its claims in the South China Sea.

The Pentagon report estimated China has reclaimed 3,200 acres (1,300 hectares) of land in the Spratly Islands, also claimed by the Philippines, over the past two years.

Attention

Beijing has been angered by the growing US attention on Asia and American forays into the Sea, including sailing warships close to reclaimed islands.

“It is the United States that has been flexing military muscles by frequently sending military aircraft and warships to the region,” a Chinese defence ministry spokesman told state media following the report.

Two Chinese fighter jets carried out an “unsafe” intercept of a US military reconnaissance aircraft over the South China Sea, the Pentagon said on Wednesday, drawing a rebuke from Beijing, which demanded that Washington end surveillance near China.

The incident, likely to increase tension in and around the contested waterway, took place in international airspace on Tuesday as the US maritime patrol aircraft carried out “a routine US patrol,” a Pentagon statement said.

The encounter comes a week after China scrambled fighter jets as a US Navy ship sailed close to a disputed reef in the South China Sea.

Another Chinese intercept took place in 2014 when a Chinese fighter pilot flew acrobatic maneuvers around a US spy plane.

The intercept occurred days before President Barack Obama travels to parts of Asia from May 21-28, including a Group of Seven summit in Japan and his first trip to Vietnam.

China claims most of the South China Sea, through which $5 trillion in ship-borne trade passes every year. The Philippines, Vietnam, Malaysia, Taiwan and Brunei have overlapping claims.

Washington has accused Beijing of militarizing the South China Sea after creating artificial islands, while Beijing, in turn, has criticized increased US naval patrols and exercises in Asia.

The Pentagon statement said the Department of Defense was addressing the issue through military and diplomatic channels.

China’s Foreign Ministry spokesman Hong Lei said the US statement was “not true” and that the aircraft had been engaging in reconnaissance close to China’s island province of Hainan.

“It must be pointed out that US military planes frequently carry out reconnaissance in Chinese coastal waters, seriously endangering Chinese maritime security,” Hong told reporters at a regular press briefing on Thursday.

“We demand that the United States immediately cease this type of close reconnaissance activity to avoid having this sort of incident happening again,” Hong said, adding that the actions of the Chinese aircraft were “completely in keeping with safety and professional standards”.

“They maintained safe behavior and did not engage in any dangerous action,” Hong said.

China’s Defense Ministry said in a fax that it was looking into reports on the incident.

The Pentagon has yet to release the precise location of the encounter.

In 2015, the United States and China announced agreements on a military hotline and rules of behavior to govern air-to-air encounters called the Code for Unplanned Encounters at Sea (CUES).

“This is exactly the type of irresponsible and dangerous intercepts that the air-to-air annex to CUES is supposed to prevent,” said Greg Poling, director of the Asia Maritime Transparency Initiative at Washington’s Center for Strategic and International Studies think-tank.

Poling said either some part of China’s airforce “hadn’t gotten the message”, or it was meant as a signal of displeasure with recent US freedom of navigation actions in the South China Sea.

“If the latter, it would be very disappointing to find China sacrificing the CUES annex for political gamesmanship.”

Zhang Baohui, a security expert at Hong Kong’s Lingnan University, said he believed the encounter highlighted the limitation of CUES, and shows that Chinese pilots would still fly close to US surveillance planes if needed.

“Frankly, we’re always going to see these kinds of incidents as China will always put the priority on national security over something like CUES whenever it feels its interests are directly threatened,” he said.

While the precise location of the encounter is not yet known, regional military attaches and experts say the southern Chinese coast is a military area of increasing sensitivity for Beijing.